System and method of registering the identity of a telephone terminal in association with the identity of a computer terminal

ABSTRACT

In a Computer Telephony Integration environment, to reduce the risk of inadvertent or fraudulent registration of the association of a user&#39;s computer terminal with the wrong telephone, i.e. one other than the telephone adjacent to the computer terminal or the user&#39;s mobile telephone, a host computer instructs the user via a screen display to call a particular extension of a CTI-enabled PABX. When a call to that extension is detected, the PABX treats the call as having been answered, and reports this to the host computer. The user is now instructed to dial a codeword, and when this is received at the PABX and reported to the host computer, the telephone is registered as associated with the computer terminal provided that the reported codeword matches the codeword provided to the user. A number of variants and refinements provide for greater security against fraudulent registration.

BACKGROUND OF THE INVENTION

This invention relates to a Computer Telephony Integration (CTI)environment wherein, for example, a user can enter a command at hiscomputer terminal for a call to be made to a destination number.

DESCRIPTION OF RELATED ART

Examples of such CTI environments are disclosed in the articles“Introduction to Computer Telephony Integration”, by A. Catchpole, G.Crook, and D. Chesterman, British Telecommunications Engineering, July1995; “Computer Telephony Integration—The Meridian Norstar”, by A.Catchpole, British Telecommunications Engineering, October 1995;“Computer Telephony Integration—The Meridian 1 PBX”, by P. Johnson, A.Catchpole, and L. Booton, British Telecommunications Engineering, July1996; “Callscape—Computer Telephony Integration for the Small Business”,by G. Hillson, G. Hardcastle, and M. Allington, BritishTelecommunications Engineering, January 1997, and “Call Centres—DoingBusiness by Telephone” by M. Bonner, British TelecommunicationsEngineering, July 1994.

CTI is particularly useful in call centres, and InternationalApplication Number PCT/GB96/00727 (Publication Number WO 96/31044) inthe name of BRITISH TELECOMMUNICATIONS public limited company (BT)discloses an ACD suite in a call centre such as BT's national telephoneaccount management operation.

In such a call centre, if an agent wants to be connected to the numberof a target customer, for example a potential customer in a telesalesmode of the call centre, the agent sends a “make call” command to thecall control apparatus. If the agent is allowed to specify a desirednumber, referred to as the target number, then he will insert this intothe command. Otherwise, upon receipt of a make call command that doesnot contain a target number, the call control apparatus will generate asuitable number using a sales program as is known in the art. The callcontrol apparatus will then send to the switching system a commandcontaining a target number and the number of an extension which is to bejoined to the external call to the target customer. The extension andthe target customer are now connected together by the switching systemso that the agent may speak to the target customer. Depending upon thecontrol program of the switching system, this is effected by any one ofa number of known ways. For example, in one way the switching systemmakes an external call to the supplied target number, and, when thetarget customer answers, then makes a call to the extension, and joinsthe two calls when the agent answers the call to the extension, and inanother way the switching system makes a single call from the extensionto the target number.

If the call control apparatus has registered an association between theagent and an extension number other than the number of the telephoneterminal that is associated with the computer terminal to form aworkstation, as is known in the art, then the wrong agent will beconnected to the target customer.

BRIEF SUMMARY OF THE INVENTION

In accordance with a first aspect of the present invention, there isprovided a method of registering the identity of a telephone terminal inassociation with the identity of a computer terminal, the methodcomprising the steps of:

providing to a user of the computer terminal, via that computerterminal, the identity of a predetermined destination terminal number;

answering a call made to that predetermined destination terminal number;

receiving at that predetermined destination terminal number the identityof a telephone terminal from which that call was made;

providing to the user, via that computer terminal, a codeword;

receiving at that predetermined destination terminal data provided bythe user via that telephone terminal;

comparing the received data with the provided codeword; and

if there is a match, registering the identity of that telephone terminalin association with the identity of that computer terminal.

The secure registration in accordance with the present invention of atelephone terminal with a computer terminal brings advantages in anumber of fields.

In a call centre, since the call control apparatus registers theidentity of the telephone terminal that makes the call, herein referredto as a registration call, to the predetermined destination terminalnumber, in this particular case an extension of the switching system, itwill normally be only the agent at the computer terminal who will knowthe codeword, e.g. from the screen display, and who will make theregistration call from his chosen terminal, which may be the extensionat the workstation, or it may be his mobile telephone. Therefore, unlessa situation is contrived in which a registration call, using thatparticular codeword, is made to the predetermined extension from aterminal other than a terminal which will be normally answered by theagent, the call control apparatus will always register the correcttelephone terminal identity in association with the computer terminaland the agent identity.

In a conventional office environment, a user can use his computerterminal to request an outgoing call, and a CTI controller will commanda PABX serving the office to make a call from the extension registeredin association with that computer terminal.

The present invention also makes receipt of incoming calls secure. Forexample, a remote originator can either request registration informationfrom a user's computer terminal, or be sent it unsolicited, and make acall to the telephone number of that registration information, i.e. theidentity of the telephone terminal associated with that computerterminal. Depending upon the particular commands used in the signallingprotocol, the identity of the telephone terminal may be the soleinformation in a message sent to the remote originator, or it may beassociated with other information.

The registration information may be stored in the computer terminal, orit may be stored remote from the computer terminal, for example in ahost computer associated with the computer terminal.

The step of providing the identity of a predetermined destinationterminal number may be performed upon detection of a make call commandmade via that computer terminal.

In accordance with a second aspect of the present invention, there isprovided a system for registering the identity of a telephone terminalin association with the identity of a computer terminal, the systemcomprising:

means to provide to a user of the computer terminal, via that computerterminal, the identity of a predetermined destination terminal number;

means to answer a call made to that predetermined destination terminalnumber;

means to receive the identity of a telephone terminal from which thatcall was made;

means to provide to the user, via that computer terminal, a codeword;

means to receive data provided by the user via that telephone terminal;

means to compare the received data with the provided codeword; and

means responsive to a match between the received data and the providedcodeword to register the received identity of that telephone terminal inassociation with the identity of that computer terminal.

The means to provide the identity of a predetermined destinationterminal number may be arranged such as to provide said identity of apredetermined destination terminal number upon detection of a make callcommand invoked by the user.

The means to provide the identity of a predetermined destinationterminal number; the means to provide to the user, via that computerterminal, a codeword; the comparing means; and the registering meanstogether may constitute a subsystem; and

the answering means; the means to receive the identity of a telephoneterminal; and the means to receive data provided by the user togethermay constitute a separate subsystem.

BRIEF DESCRIPTION OF THE DRAWINGS

Specific embodiments of the invention will now be described by way ofexample with respect to the accompanying drawings in which:

FIG. 1 shows a known ACD suite; and

FIG. 2 shows an embodiment of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE INVENTION

In FIG. 1 there is shown a known ACD suite used in a call centre such asBritish Telecommunications' national telephone account managementoperation. The ACD suite and its operation is described in detail inInternational Application Number PCT/GB96/00727 (Publication Number WO96/31044) and for the purposes of the present invention will bedescribed only briefly in respect of its component parts, and relevantoperational characteristics.

The suite comprises a PABX 10, constituting a switching system of thepresent invention, associated with an ACD system 12 and connected to anIntegrated Services Digital Network (ISDN) 14 by a primary rate ISDNlink 16 having thirty 64 kbit/s channels. Customers, represented bytelephone terminal 18, can make calls to the call centre by dialling thepublished directory number, also referred to as a national number or adestination terminal number, of the call centre. These incoming callsare received at the PABX 10 and placed in a queue by the ACD system 12.The ACD system 12 in known manner allocates the call at the head of thatqueue to a selected one of a plurality of call centre agent positions.The agents are either call centre-based at positions 20 (also referredto as workstations), each comprising a telephone terminal 22 (alsoreferred to as an ACD turret) and an associated computer terminal 24, orthey are teleworking agents, represented by remote workstation 21comprising telephone terminal 36 and associated computer terminal 38.

Each computer terminal 24 is constituted by a personal computer,commonly referred to as a PC, and is connected to a host computer 26having an associated database 28 and connected to the PABX 10 via a CTIlink 30. An interactive voice response system (IVR) 32 is connected to aport of the PABX 10 and to the host computer 26, and is arranged toobtain data from customers, and teleworking agents, and to pass this tothe host computer 26 for processing as appropriate. In FIG. 1 only twoworkstations 20 are shown although in a call centre of a large companythere may be in the region of a hundred workstations 20. In variants,the computer terminals 24 are dumb terminals and rely on the processingpower of the host computer 26.

The location of a remote workstation 21 could be one of a variety ofplaces. For the purpose of this example it will be assumed that theremote workstations 21 are located in the private residences ofteleworking agents, and are connected to the ISDN 14 via respectivebasic rate ISDN links 40. The ISDN links 40 provide two independent 64kbit/s (B) channels and a 16 kbit/s (D) data channel. Thus calls can bemade and charged independently from each of the terminals 36 and 38. Thehost computer 26 is connected to the ISDN 14 via a primary rate ISDNlink 42. In variants the link 42 is a basic rate ISDN link.

When an agent starts a work period at a workstation 20, or at a remoteworkstation 21, he or she logs on to the ACD system 12 using theTouchTone (Registered Trade Mark) keypad of the telephone terminal 22,36. Alternatively, the log on procedure can be performed via thecomputer terminal 24, the host computer 26 and the CTI link 30, or viathe computer terminal 38, the ISDN 14, the link 42, the host computer 26and the CTI link 30.

The host computer 26, constituting a call control apparatus of thepresent invention, is programmed to monitor activity of the call controlprocessor (not shown) of the PABX 10 and to send command messages to thecall control processor as will be described below.

The host computer 26 contains a list of the identities of, say, tenvirtual terminals 34 which are designated as virtual turrets forteleworking only and have no physical existence. In this example, thePABX 10 is configured so that it has a set of port identitiescorresponding to the identities of the virtual terminals 34, these portidentities not being associated with any physical ports of the PABX 10and being merely virtual ports. In other words, the call controlprocessor will command connection of the ringing current generator to aselected virtual port under the control of the ACD 12, and cease theconnection under the control of the host computer 26, but the PABX 10will not be aware that these virtual ports have no physical existence.

In order to support teleworking, the ACD system 12 must still associatea teleworking agent's identity with the identity of what it deems to bean active terminal 22 in the call centre, and the manner in which thisis achieved will now be described.

In a first situation, a teleworking agent will activate his or hercomputer terminal 38 which will autodial the directory number of thehost computer 26. A connection (using one of the B channels) may beestablished via the ISDN 14.

A teleworking agent logs on to the host computer 26 using anidentification protocol including informing the host computer 26 of thedirectory number being currently used by the teleworking agent, and thehost computer 26 will store the teleworking agent's directory number inassociation with the identity of the teleworking agent.

The host computer 26 will now select an available terminal 34 from itslist of virtual turrets, associate the teleworking agent's identity withthe identity of the selected terminal 34, and send them to the ACDsystem 12 via the CTI link 30. The host computer 26 now has a recordassociating the identity of the agent, the identity of the remoteterminal, and the identity of the selected terminal 34 and can uponinterrogation by the identity of a terminal 34 retrieve the identity ofthe corresponding remote terminal.

The ACD system 12 now includes within its list of active agents, anentry for that selected terminal 34 associated with the teleworkingagent's identity, and when the ACD system 12 allocates that selectedterminal 34 to receive an incoming call, the PABX 10, under the controlof the ACD system 12, attempts to connects the call to the correspondingvirtual port.

respective line card (not shown) and applies ringing current to theselected terminal 34 and ringing tone to the incoming call,

The host computer 26 detects that the PABX 10 has connected a call to avirtual port which is recorded as being a teleworking virtual terminal,and responds by commanding the PABX 10 to treat the selected terminal 34as having gone off-hook, i.e. as being answered, and thereby ceaseapplying ringing current to it, and to make an outgoing call to thedirectory number associated with the selected terminal 34 in the recordstored in host computer 26, this being the teleworking agent'stelephone.

When the host computer 26 detects that the PABX 10 has registered thatthe remote teleworking agent has answered this outgoing call, the hostcomputer 26 then instructs the PABX 10 to join the incoming call to theoutgoing call, by for example a conference bridge.

The ACD system 12 could be an integral part of the call control processof the PABX 10 or could be a separate entity and coupled to the PABX 10via a suitable link.

As shown in FIG. 2, the PABX 10 has a further virtual terminal 34′,identical with a terminal 34 but not forming part of the set of virtualterminals 34 used by the host computer 26 in association with theidentities of teleworking agents, as described above.

The secure registration of telephone terminal/computer terminalassociation of the present invention is effected as follows.

Consider first the situation of a local agent, i.e. one working at aworkstation 20 whose telephone is directly connected to a port of thePABX 10. The host computer 26 is arranged to respond to initiation of alog on procedure by the agent via the keyboard of the computer terminal24 at his workstation 20 to send to that computer terminal 24 data for ascreen display containing a text message “Please dial extension XXXX.When the call is answered, please enter via your telephone keypad thecodeword YYYY.”.

The agent now responds to the message by dialling on his telephone 22,referred to herein as making a registration call, the extension XXXX,which is the extension number corresponding to the virtual terminal 34′,and the PABX 10 responds in normal manner by connecting ringing currentto the corresponding port. The host computer 26 knows, via the CTI link30, that the virtual terminal 34′ is “ringing”, and instructs the PABX10 to treat the call as answered by recording the corresponding linecircuit as being in “off hook” condition, and to report any digitsreceived at the PABX 10 for that call.

The PABX 10 is arranged, in known manner, to collect digits dialledduring the call, i.e. any keypresses made by the user, including “*” and“#”. In a variant, the PABX 10 connects a digit collector, not shown, tothe virtual terminal 34′.

Upon receipt of a message from the PABX 10 containing the digitsreceived from the agent, and the extension number of the telephone 22from which they were sent, the host computer 26 compares these receiveddigits with the code sent in the screen display information, and, ifthey match, stores the extension number in association with the identityof the computer terminal 24 and sends a further screen display to thecomputer terminal 24 containing the text message “Please hang up.”. Theagent has now been registered at the host computer 26 in associationwith his telephone terminal 22 and his computer terminal 24.

In a variant, the host computer 26 sends to the computer terminal 24data for a first screen display containing a text message “Please dialextension XXXX.”, and commands the PABX 10 to answer the call and reportback to the host computer 26 the identity, i.e. the extension number orcalling line identity (CLI), of the terminal that makes that call to theextension XXXX. On receipt of this identity the host computer 26 recordsthis identity in association with the identity of the computer terminal24, and sends data for a second screen display containing a text message“Please enter via your telephone keypad the codeword YYYY.”. Thisprovides increased security by making it more difficult for an errantagent to cooperate with a collaborator to attempt to register atelephone which is remote from the computer terminal instead of thetelephone which is adjacent to that computer terminal. If the codewordis not sent to the computer terminal until a telephone is detected ashaving established a connection with the extension XXXX, then the agentat the computer terminal will not be able to make a telephone call viathe PABX 10 to the collaborator at that remote telephone to pass thecodeword.

In a refinement of this last-mentioned variant, the host computer 26starts a timeout of a few seconds when it sends the second screendisplay and ignores any digits received from the PABX 10 after thetimeout has matured.

In another variant in which the computer terminal 24 has a sound cardand a loudspeaker, or a pair of loudspeakers, the host computer 26 sendsthe first screen message as mentioned above, and upon receipt of theidentity of the terminal that makes the call to the extension XXXX,sends a screen message “Place the telephone handset against the computerloudspeaker, and press any key.”. In response to the key press made bythe agent the host computer 26 now sends a command to that computerterminal to generate the codeword as an audio signal using standard MF4(multi-frequency) signalling tones. The PABX 10 receives these tones andtreats them in the same manner as tones generated by key presses on thetelephone instrument, i.e. decodes them using its digit collector. Thisprovides a further level of security in that only a telephone terminal,either fixed or mobile, at that computer terminal can be used to relaythe codeword to the extension XXXX, and reduces the likelihood of theerrant agent using mobile telephones to transfer the codeword to thecollaborator or directly to the remote telephone.

In a refinement to reduce further the likelihood of a fraudulentregistration being set up through the use of mobile telephones by anerrant agent and a collaborator, the host computer 26 sends a command tothe PABX 10 for a speech synthesiser to generate “spoken” digits forconnection to the extension which has called the extension XXXX. Theagent hears the digits, either via the handset or via a loudspeakerfacility, and immediately keys these digits on the keyboard of hiscomputer terminal. This may be repeated one or more times with differentdigits being generated by the host computer. If the measured timedifference between the time that the command is sent to the PABX 10 andthe time that the agent enters the digits on the keyboard is more than apredetermined limit, then the registration procedure is recorded asinvalid. This will reduce the likelihood of a fraudulent registrationthrough the collaborator hearing the digits and relaying them to theagent. If the collaborator tries to avoid a relay delay by coupling hismobile telephone to the extension, i.e. providing a direct transmissionto the mobile telephone of the agent, a further refinement provides thata sequence of such synthesised words randomly instructs the agent toenter digits via the telephone or the keyboard, e.g. “five, seven,keyboard”; “one, three, telephone”. This makes it difficult for thecollaborator, since to reduce the relay delay he needs to have goodcoupling between the extension receiver and the mobile transmitter,which reduces his ability to hear the instruction himself, as he may berequired to enter the digits at that extension.

Because the time for which the called PABX extension, i.e. XXXX in theabove examples, is in use for the registration procedure is only a fewseconds, in a variant the host computer 26 refers to its internal recordof the busy/free status of the PABX extensions, makes a random selectionfrom the free extensions for use in the registration procedure, andcommands the PABX 10 in respect of the selected extension in the samemanner as described above for the extension XXXX. This will notinconvenience any agent at the selected extension since the PABX 10 willtreat the call as answered and disconnect the ringing current generatorbefore any, or any significant, audible sound can be produced at thatselected extension.

The importance of having a secure registration of the workingassociation of the extension and the computer terminal used by the agentis that in this type of CTI environment the agent makes a call bysending an instruction, including the desired destination number, to thehost computer 26, which responds by sending an instruction containingthat destination number and the extension number currently registered asbeing associated with the agent's computer terminal 24 to the PABX 10 tocommand it to make an external call to the destination number, and alsoto make a call to that extension number, and to join the two calls. Thusthe agent is then in communication with the user at that destinationnumber.

In variants, the host computer 26 commands the PABX 10 to make theexternal call using the agent's telephone terminal as originatingterminal, and the destination number as recipient terminal, and in thisway only a single call is made, as opposed to the “two call/joining”method described above.

If the host computer 26 is storing an erroneous association oftelephone/computer, then the PABX 10 will ring an extension other thanthe one at which the agent is currently working. This erroneousassociation may arise through, for example, inadequate updatingprocedures and be entirely innocent. On the other hand, without thesecure association process of the present invention, an agent wouldmerely inform the host computer 26 of the extension of his telephone 22,and this provides an opportunity for deliberate or inadvertent misuse ofthe system. An example of this would be where an agent informs the hostcomputer that he is currently working at extension ZZZZ, which is theextension of, say, the director of the company employing the agents. Theagent could then instruct the host computer 26 to make a call to somenational number, and the PABX 10 would then make the external call and acall to extension ZZZZ, and join the calls. Alternatively, as describedherein, the PABX 10 can make a single call using the extension ZZZZ asthe originating terminal.

The secure registration procedure of the present invention ensures thatthe host computer 26 stores the correct association. By providing thecodeword to the computer terminal 24 at which the agent has logged on,it is reasonable to suppose that that agent, and no other person, canread the screen message and know that codeword. So even if thatextension number XXXX becomes generally known, it will not be possiblein normal use, for the agent to make the call to extension XXXX, andenter the code read from the screen, at any telephone other than the oneadjacent to the agent's computer terminal 24. For increased security,the host computer 26 can send the message in two parts. In this case, afirst part “Please dial extension XXXX.” is displayed, and the hostcomputer 26 will wait for a message from the PABX 10 that ringingcurrent is being supplied to extension XXXX, and will then send thesecond part “When the call is answered, please enter via your telephonekeypad the codeword YYYY.”. In a variant the host computer 26 respondsto that message from the PABX 10 in the normal manner by instructing thePABX 10 to record the line circuit as being off hook, and then sends theagent a second message part “Now please enter via your telephone keypadthe codeword YYYY.”.

It will be appreciated that the host computer 26 can generate thecodewords using a one time pad, i.e. a pseudo-random process forgenerating a codeword. Such processes are well known and will not bedescribed further.

For the situation of a teleworking agent, the host computer 26 isarranged to respond to initiation of a log on procedure by theteleworking agent via the keyboard of a computer terminal 38 at aworkstation 21 to send to that computer terminal 38 data for a screendisplay containing the text message “Please dial destination number AAAABBB XXXX. When the call is answered, please enter via your telephonekeypad the codeword YYYY.”.

The teleworking agent responds using a land-based telephone terminal, ora mobile telephone terminal, and the PABX 10 sends a message to the hostcomputer 26 containing the digits received from the teleworking agenttogether with the CLI sent from the telephone terminal used by theteleworking agent.

In like manner, the host computer 26 compares these received digits withthe code of the screen display, and if they match stores, i.e.registers, the CLI in association with the identity of the computerterminal 38 and sends a further screen display to the computer terminal38 containing the text message “Please hang up.”. The CLI and computerterminal identity are stored in respective fields of a registrationrecord.

In a variant, the host computer 26 does not refer to stored informationto make an assumption as to whether the agent is at a PABX extension orat a remote telephone, but sends a composite screen display “Please dialextension XXXX, or destination number AAAA BBB XXXX, as appropriate.When the call is answered, please enter via your keypad the securitydigits YYYY.”.

In another variant, at the start of the registration procedure, the hostcomputer 26 refers to the registration record for the computer terminal,reads any existing CLI stored in the CLI field, and generates a screendisplay to inform the agent of the last-registered CLI. Included in thisscreen display is the instruction to choose between options “Useexisting registration” or “Change existing registration”. If the userselects “Use existing registration”, the registration procedure is notused. In a further variant, an alternative screen display is generatedwhich informs the user of the existing registered CLI, and instructs theuser to proceed with the registration procedure as verification of thatregistration.

If there is no existing CLI stored in the CLI field, this screen displayis not generated, and the normal registration procedure is performed.

As just described, this method of registering the working association ofa telephone terminal and a computer terminal is performed at log on ofthe agent, i.e. at the start of a working session. In variants, theregistration is performed only if the agent indicates to the hostcomputer 26 that he wants to make a call. Regardless of whenregistration is performed, it can be persistent or non-persistent. Apersistent registration lasts until de-registration occurs eitherautomatically upon termination of the current session, or when ade-registration command is entered or a new registration is performed.In this latter case, the registration is semi-permanent, and is changedonly when, for example the agent currently associated with theworkstation changes his mobile telephone and has a new number, or theworkstation becomes associated with a different agent who registers hismobile telephone number instead of the out-of-date registration of thesuperseded agent.

If the telephone terminal 36 does not have a TouchTone dial, theteleworking agent can speak the digits of the codeword and the IVR 32will perform voice recognition to identify the spoken digits and sendthem in digital form to the host computer 26. Instead of the IVR 32, anoperator at an operator position of the PABX 10 can listen to the spokendigits and key them into an operator's keypad connected directly, orindirectly, to the host computer 26.

Whereas in the above-described embodiment the agent is instructed tomake call to an extension of the PABX 10 at which the codeword will bereceived, it is not necessary for the switching system to be local tothe agent, and it can be remotely situated. The CTI controller for thePABX can be local to the PABX, or remote and coupled to it via a datalink.

Although the above description is in respect of a call centre, it willbe appreciated that the invention is applicable to any CTI environmentinvolving a computer terminal attached to a host computer.

The destination number which a user calls and sends the codeword to neednot be an extension on a local PABX, or a remote PABX, but can be thenumber of an ordinary direct exchange line at which an intelligentterminal is connected, e.g. one having a CTI card. This terminal can bearranged to answer incoming calls automatically, to collect the CLI andthe codeword, and to send a message via a data link back to the user'scomputer terminal. This data link can be a dedicated link via a datanetwork, or via modems and the public switched telephone network.

Furthermore, the invention is not limited to outgoing calls made by usercommands via the computer terminal, e.g. by keyboard entry or byclicking, in the usual manner with a mouse, on a number or namedisplayed on the screen of the computer terminal.

The registered association of the present invention can be used wherethe computer terminal is coupled to another such computer terminal via adata link. An example is where the computer terminals are connected foraccess to the Internet. Assuming that a first user has performed aregistration at his Web server of the working association of histelephone terminal and his computer terminal, and that subsequently hefinds a Web page relating to a second user and containing a “Call Me”link, the “Me” in this sense meaning the first user. The first userclicks on the “Call Me” link, which causes his computer terminal,referred to as the first computer, to send a “Call Me” message to hisWeb server, referred to as the first server, containing the identity ofthe registered associated telephone terminal. The first server knows theidentity, i.e. the network address, of the computer associated with theWeb page, referred to as the second computer, and forwards the “Call Me”message to the second computer via a Web server, referred to as thesecond server, associated with the second computer.

On receipt at the second computer of the “Call Me” message, a screendisplay is generated to inform the second user that a telephone call tothe displayed telephone number has been requested. The second user cannow make a conventional call via his telephone terminal to that number.Alternatively, if the second user is associated with a CTI-enabledswitching system, he can enter a make call command at the secondcomputer to effect a call to that displayed telephone number. The firstand second servers can be constituted by a single server, for example aserver in the call centre of a mail order catalogue company. The firstuser can request Web pages from the call centre server and click on a“Call Me” button, thus sending a message to the server. The server notesthe first user's computer identity, looks up the associated telephonenumber, and instructs the call centre's telephone system to call theuser's telephone.

Another example of CTI environment other than a call centre is aconventional office, provisioned with a telephone terminal and acomputer terminal, which does not in itself limit the user to anyparticular profession or work practice. The computer terminal has atelephone directory program which can be searched by the user, and whena desired telephone number has been found, the user will click his mousebutton on the number. This will cause the digital data relating to thedisplayed number to be sent from the computer terminal, or from its hostcomputer depending upon the arrangement, to a PABX serving the office.The PABX now acts, as described above, and makes a call from the numberrecorded by the host computer as associated with that computer terminalto the requested number.

In the above-described registration procedures the instructions areprovided to the user by means of a screen display at his computerterminal. Instead, where a computer terminal has a sound card andloudspeakers, a speech synthesiser can be used to generate “spoken”instructions.

In the above-described embodiment of the present invention, the hostcomputer 26 constitutes means to provide to a user of a computerterminal, via that computer terminal, the identity of a predetermineddestination terminal number; means to provide to the user, via thatcomputer terminal, a codeword; means to compare received data with theprovided codeword; and means responsive to a match between the receiveddata and the provided codeword to register the received identity of atelephone terminal in association with the identity of that computerterminal. Also, the PABX 10 constitutes means to receive data providedby the user via a telephone terminal, and means to receive the identityof a telephone terminal from which that call was made; and the PABX 10together with the host computer 26 constitute means to answer a callmade to that predetermined destination terminal number.

What is claimed is:
 1. A method of registering the identity of atelephone terminal in association with the identity of a computerterminal, the method comprising: providing to a user of the computerterminal, via that computer terminal, the identity of a predetermineddestination terminal number; answering a call made to that predetermineddestination terminal number; receiving at that predetermined destinationterminal number the identity of a telephone terminal from which thatcall was made; providing to the user, via that computer terminal, acodeword; receiving at that predetermined destination terminal dataprovided by the user via that telephone terminal; comparing the receiveddata with the provided codeword; and if there is a match, registeringthe identity of that telephone terminal in association with the identityof that computer terminal.
 2. A method as claimed in claim 1, whereinproviding the identity of a predetermined destination terminal number isperformed upon detection of a make call command made via that computerterminal.
 3. A system for registering the identity of a telephoneterminal in association with the identity of a computer terminal, thesystem comprising: means to provide to a user of the computer terminal,via that computer terminal, the identity of a predetermined destinationterminal number; means to answer a call made to that predetermineddestination terminal number; means to receive the identity of atelephone terminal from which that call was made; means to provide tothe user, via that computer terminal, a codeword; means to receive dataprovided by the user via that telephone terminal; means to compare thereceived data with the provided codeword; and means responsive to amatch between the received data and the provided codeword to registerthe received identity of that telephone terminal in association with theidentity of that computer terminal.
 4. A system as claimed in claim 3,and wherein the means to provide the identity of a predetermineddestination terminal number is arranged to provide said identity of apredetermined destination terminal number upon detection of a make callcommand invoked by the user.
 5. A system as claimed in claim 3, andwherein: the means to provide the identity of a predetermineddestination terminal number, the means to provide to the user, via thatcomputer terminal, a codeword, the comparing means, and the registeringmeans together constitute a subsystem; and the answering means, themeans to receive the identity of a telephone terminal, and the means toreceive data provided by the user together constitute a separatesubsystem.